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OCCURRENCE OF A LEPIDOPTERAN SPECIES SAMIA CYNTHIA
DRURY ON PRIMARY HOST PLANT SPECIES LITSEA MONOPETALA
ROXB. OF MUGA SILKWORM IN DISTRICT BAGESHWAR,
UTTARAKHAND, INDIA
D. P. Paliwal, Chandrakanta1*, A. K. Paliwal2, Deepa Kumari3 and Garima Joshi3
Central Silk Board, Research Extension Centre, Bageshwar (Uttarakhand), India.1Department of Botany, Govt. P.G. College, Bageshwar (Uttarakhand), India.
2Department of Botany, S. B. S. Govt. P. G. College, Rudrapur, Udham Singh Nagar (Uttarakhand), India.3Department of Zoology, Govt. P.G. College, Bageshwar (Uttarakhand), India.
Abstract
The present study deals with the occurrence of wild silkmoth Samia cynthia Drury on nature grown one of the primary host
plant species Litsea monopetala Roxb. of muga silkworm species Antheraea assamensis Helfer, which is exclusively cultivated
in Assam for production of precious muga silk fibre in India only in the world. The detailed biology of insect was carried out
on nature grown host plant under natural weather in District Bageshwar of State Uttarakhand, India. The incidence of the wild
silk moth recorded during onset of winter at an altitude of 3000ft. The larval period on an average recorded 30 days. The spun
cocoons were in tan-brown colour and the average cocoon weight for male and female was recorded 1.5g and 1.92g,
respectively.
Key words : Samiya cynthia Drury, silkworm, host and spin.
Plant Archives Vol. 15 No. 1, 2015 pp. 89-91 ISSN 0972-5210
Introduction
A large number of wild silkworm species belong to
the family Saturniidae. This family has great economic
importance as it consist a large number of wild silk
producing species. Presently, around eighty wild silk
producing species feed on various host plants have been
reported (Jolly et al., 1975). Among them three species
i.e. Antheraea paphia L. (Indian Tasar moth), A.
assamensis Helfer (Indian Muga moth) and Samia
cynthia Drury (Indian Eri moth) are being exploited for
producing commercially valued silk production.
S. cynthia Drury of Saturniinae is native to China,
where its caterpillars feed on the Tree of Heaven,
Ailanthus altissima and very closely related to Samia
ricini, the Eri silkworm. Apart from the aforesaid host
plant species of the insect other plant species i.e.
Ailanthus sp., Aithaea rosea Cav., Apium graveolans
L., Azadiracht indica A. Juss., Berberis sp., Carica
papaya L. etc have also been reported as host of the
insect in the world.
Under the present communication as new host plant,
Litsea monopetala Roxb. (Syn. Litsea polyantha Juss.)
is recorded for S. cynthia (Drury) in Bageshwar
(Uttarakhand), India.
District Bageshwar is located at 29º51’N latitude and
79º46’E longitude with an elevation of at 800 AMSL in
state Uttarakhand and consists varied topography with
high mountain peaks, ridges and river valleys with an
altitude ranging from 800 to 6,000 m. The area covers all
weather conditions like tropical, sub-tropical, sub-
temperate and temperate. Because of this district has
affluent flora and fauna and several wild silkworm species
are found abundantly in the forest areas of the Distt.
In the present study, insect biology of S. cynthia
Drury on its new host L. monopetala Roxb. has been
carried out.
Earlier work
There are number of studies have been reported on
seri-biodiversity and their wide potential as a source of
natural silk in Indian subcontinent (Arora and Gupta, 1979;
Thangavelu, 1991; Nassig et al., 1996; Chinnaswamy,*Author for correspondence : E-mail: [email protected]
90 D. P. Paliwal et al.
2001; Thangavelu et al ., 2002; Srivastava and
Thangavelu, 2005). Jolly et al. (1975) recorded
approximately 80 species in Asia and Africa producing
silk of commercial importance. Arora and Gupta (1979)
enlisted nearly 40 species in India alone.
Materials and Methods
The larvae of the insect species were brushed on
the host plant and reared under net cover in open weather
till maturation and further cocooning of the worms. The
spun cocoons were collected and kept indoor weather
conditions for emergence, coupling and oviposition. The
observations in respect of biology of the insect were
recorded.
Results and Discussion
The wild silkmoth Samia cynthia (Drury), a member
of Saturniidae family (Subfamily : Saturniinae) belonging
to order Lepidoptera is commonly known as Ailanthus
silkmoth is univoltine and polyphagus in nature as it covers
one crop cycle.
The morphometrics of different stages of the insects
have been depicted (figs. 1a-e).
Eggs
Eggs are white creamish in colour, laid in rows of 10
to 20 on leaves and measures around 1 × 1 mm in size.
Hatching takes 7–10 days.
Larvae
The newly-hatched, 4 mm long larvae consume part
of their egg shells. At this stage they are mainly yellow
with black-tipped, conical tubercles, black legs and a black
head, which is carried almost horizontal. The body bears
longitudinal rows of black spots. In the second instar, the
body colour becomes paler with the cervical shield
a b c
d e
Fig. 1 : Biology of insect Samiya cynthia Drury.
(a) Insect larva feeding on L. monopetala Roxb. leaves (b) Mature larva
(c) Cocoon (d) Female moth
(e) Laid eggs
Occurrence of a Lepidopteran Species S. cynthia on Primary Host Plant Species L. monopetala 91
reduced to a pair of black stripes. In the third instar, the
head becomes retractible, the body pale yellow, the dorsal
and dorso-lateral tubercles white. These tubercles loose
their black tips but little black areas appear on the anal
claspers and flap. By the fourth instar the head become
pale brown, the yellowish-green body becomes covered
with a white, powdery bloom, and the legs turn chrome
yellow. In the final instar some of the body ridges become
bluish and the head greenish. Under the powdery bloom,
the body is a pale bluish-green.
Cocoons
Cocoon is spun on the leaves and its peduncle is
attached to the main petiole of a leaf of the host. Its
colour is brown to tan brown with a long peduncle at
anterior end.
Moth
The Samia cynthia moth has a brown wing color in
different shades of brown and has a beautiful purple stripe
along the wings. They also have yellow spots and lines
on the wings. At the tip of the wings is a small eye-spot
meant to distract predators. The body of the moth is white
with brown stripes. The wingspan of the moth is up to 15
cm.
Adults
Females prepare to mate in the evening or night after
emerging in late morning. Adult flight is during May and
June, as one generation.
Adult Biology
Most adults emerge in the late morning, with females
calling that same night, or even during late afternoon.
Pairing usually takes place just after sunset and lasts for
up to 12 hours. Thereafter, the female deposits eggs on
the underside of the host plants leaves.
References
Arora, G. S. and I. J. Gupta (1979). Taxonomic studies of some
of the Indian non-mulberry silkmoths (Lepidoptera :
Saturniidae). Memoirs of Zoological Survey of India, 16 :
1-63.
Chinnaswamy, K. P. (2001). Sericulture biodiversity in India.
In: M. K. Balla, S. Rayamajhi and N. M. B. Pradhan (eds.)
Participatory Biodiversity Conservation in South Asia
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Jolly, M. S., S. N. Chowdhury and S. K. Sen (1975). Non-
mulberry sericulture in India. Central Silk Board, Bombay,
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Nassig, W. A., R. E. J. Lemple and S. Keger (1996). The
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